The present invention relates to an opto-electronic integrated circuit device, an opto-electronic integrated circuit system and a transmission method using the opto-electronic integrated circuit system.
Recently, opto-electronic integrated circuit devices each including optical elements and electronic devices integrated on a substrates are proposed. In the proposed opto-electronic integrated circuit device, the elements for converting electric signals to optical signals are, e.g., laser diodes, etc., and the elements for converting optical signals to electric signals are, e.g., photodiodes, etc. The optical elements are interconnected by optical fibers, etc., and the electronic devices are interconnected by electric interconnections.
Such opto-electronic integrated circuit device, which includes optical elements and electronic devices mounted on one and the same substrate, can be generally downsized and integrated.
Following references disclose the background art of the present invention.
[Patent Reference 1]
Specification of Japanese Patent Application Unexamined Publication No. 2000-114581 (pages 6–8, FIG. 1)
[Patent Reference 2]
Specification of Japanese Patent Application Unexamined Publication No. 2000-188418 (pages 4–5, FIG. 1)
[Patent Reference 3]
Specification of Japanese Patent Application Unexamined Publication No. 1995-183570 (pages 2–3, FIG. 1).
When, e.g., N (N is a natural number of 2 or more) opto-electronic integrated circuit devices thus proposed are arranged, and optical signals are transmitted among these opto-electronic integrated circuit devices, N×(N−1)/2 optical interconnections are necessary. (N−1) laser diodes and (N−1) photodiodes must be provided on each opto-electronic integrated circuit devices. Accordingly, it is not easy to form a system which enables the transmission of optical signals among a number of opto-electronic integrated circuit devices, and even when such system is formed, the system will be bulky. Then, in transmitting an optical signal from one opto-electronic integrated circuit device A to another opto-electronic integrated circuit B, it is an idea to transmit the optical signal via further another opto-electronic integrated circuit C, etc. However, in transmitting an optical signal via further another opto-electronic integrated circuit C, etc., the optical signal is converted to an electric signal, and the converted electric signal is further converted to the optical signal. Accordingly, when an optical signal is transmitted via a number of the opto-electronic integrated circuit devices, the delay of the signal is very large.